Previously people thought that red dwarfs were poor candidates. <a href="http://www.cfa.harvard.edu/news/2013/pr201305.html">http://www.cfa.harvard.edu/news/2013/pr201305.html</a> has the details: about 75 percent of the closest stars are red dwarfs and about 6 percent have earth-like planets at the right distance to be earth like (similar mass and surface temperature).